Gas operated deep well pump

ABSTRACT

DISCLOSED IS A GAS OPERATED INDUCTION PUMP FOR PUMPING LIQUIDS AND/OR SLURRIES FROM THE BOTTOM OF A WELL. AN ORIFICE IS POSITIONED ADJACENT THE BOTTOM OF THE WELL AND ENCLOSED BY A MIXING CHAMBER AND NOZZLE. INTRODUCTION OF A GAS INTO THE ORIFICE UNDER PRESSURE GREATER THAN THE HYDROSTATIC HEAD IN THE WELL CAUSES THE GAS TO PICK UP AND MIX WITH THE SURROUNDING LIQUID OR SLURRY TO GIVE &#34;BODY&#34; TO THE MIXTURE WHICH THEN PICKS UP MORE LIQUID OR SLURRY AT THE NOZZLE. THE DISCHARGE TUBE INCREASES IN SIZE TOWARD THE TOP OF THE WELL TO UTILIZE THE ENERGY OF THE EXPANDING GAS IN THE MIXTURE.

Jan. 26, 1971 L. H. SNODGRASS 3,558,240

3 GAS: OPERATED DEEP WELL PUMP Filed July 22; 1968 INVENTOR L.HARRY SNODGRASS ATTORNEYS United States Patent 3,558,240 GAS OPERATED DEEP WELL PUMP Lincoln Harry Snodgrass, New Orleans, La., assignor to Orbit Flow, Inc., Paradis, La., a corporation of Louisiana Filed July 22, 1968, Ser. No. 746,393 Int. Cl. F04f 5/22 US. Cl. 417174 2 Claims ABSTRACT OF THE DISCLOSURE Disclosed is a gas operated induction pump for pumping liquids and/ or slurries from the bottom of a well. An orifice is positioned adjacent the bottom of the well and enclosed by a mixing chamber and nozzle. Introduction of a gas into the orifice under pressure greater than the hydrostatic head in the well causes the gas to pick up and mix with the surrounding liquid or slurry to give body to the mixture which then picks up more liquid or slurry at the nozzle. The discharge tube increases in size toward the top of the well to utilize the energy of the expanding gas in the mixture.

This invention relates to a pump system which uses gas to remove liquid and/or slurry from the bottom of a well, and more particularly is directed to a gas-powered induction pump for pumping oil or other liquids from the bottom of a deep Well.

As is known, the deeper a well becomes, the more difficult it is to remove oil by pumping. In addition, the flow of a well and particularly a deep well is reduced by the collection of liquid in the bottom of the well which tends to establish a hydrostatic head retarding the seepage of oil into the well from adjacent rock formations.

The present invention avoids these difliculties by providing a novel pumping system adapted to remove liquids from the bottom of a well which system is particularly adapted for pumping relatively deep wells. The material removed from the bottom of the well by the present invention may be oil, water, slurry, or any mixture of these.

The pump of the present invention comprises an orifice positioned adjacent the bottom of the well and enclosed by a mixing chamber and nozzle. Introduction of gas into the orifice under pressure greater than the existing hydrostatic head creates a high velocity stream of gas. The mixing chamber is so designed that by use of a diverging channel and openings, it allows the stream of gas to pick up and mix with the surrounding liquid or slurry to give body to the mixture. The gas-fluid mixture is slightly compressed and given velocity by the upper end of the converging portion of the mixing chamber and nozzle where it picks up more liquid or slurry. This stream is directed through a following venturi and the venturi effect induces a fluid flow. The velocity of the gas-fluid mixture is sufficient to lift the liquid and any solids in solution with the liquid approximately 600 feet vertically. At this stage, the energy expended by the expanding gas takes over and continues the lift. To preclude reverse pressures, the delivery tube is enlarged at intervals to provide sufficient volume to accommodate the liquid and expanding gases.

The pump of the present invention is especially useful for deep well pumping where a casing and well bore is used in conjunction with delivery tubing. Since the pump head need only be submerged to be effective, it is possible to pump substantially the entire well bore dry, leaving no pressure against the rock formation. In fact, as long as gas is applied to the orifice, a slight negative pressure is formed in the Well bore. This negative pressure and normal hydrostatic head in the rock formation allows free flow of oil from the formation into the well bore increasing efficiency of flow and delivery of oil to the surface. Because there are no obstructions in the pump other than the venturi throat and there are no moving parts in the pump, any solids in solution, such as sand and the like, have free passage and can be delivered as a slurry to the surface.

It is therefore one object of the present invention to provide an improved induction pump for wells.

Another object of the present invention is to provide a novel pumping system for removing liquids and/or slurries from the bottom of wells.

Another object of the present invention is to provide a gas powered induction pump particularly suited for pumping liquids and/or slurries from deep wells.

Another object of the present invention is to provide a novel pumping apparatus for increasing oil flow into a well by almost completely eliminating any hydrostatic pressure head at the bottom of the well.

Another object of the present invention is to provide a novel gas powered induction pump incorporating a mixing chamber and nozzle to mix gas and liquid so as to give body to the propellant force and thus increase the surface effect of the high velocity stream. At the same time, the delivery is staged to increasing areas so as to utilize the expanding gas energy to continue driving liquid after the velocity of the driving column is expended.

Another object of the present invention is to provide an improved method for removing liquids and/ or slurries from a well.

These and further objects and advantages of the invention will be more apparent upon reference to the following specification, claims, and appended drawings, wherein:

FIG. 1 is a cross section through a well incorporating the novel pump and pumping system of the present invention;

FIG. 2 is an enlarged view of a portion of the well of FIG. 1 showing details of the pump in section; and

FIG. 3 is a further enlargement of a portion of the pump showing details of the pump orifice and nozzle.

Referring to the drawings, FIG. 1 shows a well, generally indicated at 10, comprising a hole drilled in the surrounding rock or earth formation 12 which well hole incorporates the usual tubular casing 14. As illustrated at 16, the bottom of the well is filled with liquid such as oil or water. While the present invention will be described in conjunction with its use in an oil well, it is understood that it is also applicable to the removal of water, particularly from deep wells.

The lower end of the casing 14 is either open or suitably perforated so that the oil 16 may flow into the well from the surrounding rock or earth strata 12. Submersed in oil 16 is the novel pump of the present invention, generally indicated at 20, which pump is connected at its upper end to a multisection delivery tube, generally indicated at 18. The upper end of the delivery tube is provided with an outlet, as indicated by the arrow 22, where the combination gas, liquid and/ or slurry mixture from the pump 20 is fed to suitable processing equipment forming no part of the present invention. Gas under high pressure (preferably compressed air) is supplied from a pressure gas source 24 by way of line 26 to a gas tube 28 extending downwardly into the well alongside delivery tube 18 and connected at its lower end to induction pump 20. The gas supplied to the pump 20 is at a relatively high pressure, i.e., is at a pressure in excess of the hydrostatic head in the well produced by the oil or other liquid 16.

Referring to FIG. 2, the bottom of the pump is provided with a screed 29 open at its lower end 30 so that 3 oil may enter the bottom of the pump from the well bore. Screed 29 is secured to the lower end of pump housing or body 32 which comprises an enlarged tubular lower end 34, a generally conical intermediate transition portion 36, and a tubular upper end 38. Mounted in the upper end of body 38 is a venturi section 40 which is in turn coupled to the bottom stage 42 of delivery tube 18 by a swage joint 44.

One side of conical intermediate section 36 of the pump body is cut away and provided with an outwardly extending flange 46 adapted to receive and support the lower end of gas supply tube 28. The lower end of the gas supply tube communicates with a pair of channels 48 and 50 in the pump body through which the pressurized gas is fed to a pump orifice generally indicated at 52. One end of channel 50 is normally sealed off by a removable plug 54 which is provided for cleaning purposes. From orifice 52, the gas passes into a nozzle generally indicated at 56 and through venturi section 40 to the delivery tube 18.

Referring to FIG. 3, pressurized gas flowing through channel 50 enters a narrow channel 58 in nozzle insert 60 and from this channel passes outwardly into the interior of ozzle 56 through a small orifice 62. The nozzle, in addition to insert 60, comprises a lower or base section 64 attached to a nozzle head 68. The nozzle base 64 is provided with a plurality of circumferentially spaced slanted passageways 70 connecting the inner chamber 72 of the nozzle with the annular chamber 74 illustrated in FIG. 2 surrounding the nozzle within pump body 32.

In operation, a high pressure gas, such as air, carbon dioxide, or the like, is introduced by the gas line or pipe 28 into the pump body 32 whereby the gas passes through the series of channels 48, 50, and 58, and the orifice 62 of FIG. 3. The gas pressure is higher than the hydrostatic head in the well bore and escapes with a high velocity through orifice 62. The surface effect of the high velocity gas picks up liquid and/or slurry which passes through screed 29 into the pump body. The liquid and/ or slurry passes into annular chamber 74 within the pump body and through slanted passageways 70 in the nozzle base (FIG. 3) Where it mixes with the pressure gas in central chamber 72 of the nozzle. The liquid or slurry gives weight or body to the mixture. The mixture of gas and liquid in turn is converted from pressure to high velocity as it passes outwardly of the nozzle tip 68. This mixed, high velocity stream acts as a propellant for picking up additional liquid and/or slurry through the conical passageway 74 before the entrance to venturi 76 in venturi section 40 and the tapered portion 78 of the nozzle tip 68. More liquid is picked up through conically extending passageway 74 due to the increased weight or body of the mixture exiting from nozzle tip 68 into the venturi 76.

The mixture of gas and liquid (and/or slurry) is carried through the venturi and through coupling 44 into the lower stage 42 of the delivery tube until the initial velocity of the propellant force is about expended.

At a point somewhere below the point where the mixture velocity is fully expended, delivery tube 18 is provided with a second swage joint 80 (FIG. 1) where lower section 42 communicates with a second section 82 having an enlarged interal cross section or diameter to increase the size of the delivery tube at this point. Because of the increased size of the delivery tube, and expanding gases, velocity is changed to pressure and the gas-liquid mixture continues to flow upwardly. As the gas continues to expand, delivery tube 18 is further increased in internal cross section by coupling the second stage 82 through a further swage joint 84 to a further stage 86 of larger internal diameter or cross section.

Delivery tube 18 may be provided with as many increased diameter stages as desired until liquid-gas mixture reaches the top of the well and is supplied to outlet 22.

It is apparent from the above that the present invention provides an improved induction pump particularly designed to pump liquids, such as oil or water, from the bottom of a well and especially a deep well where it is difficult to raise liquid substantially large distances. Because of the absence of moving parts and the minimum number of obstructions in the pump, liquid-solid mixtures or slurries, such as oil mixed with sand, are readily raised by the pumping system of this invention. Incorporated in the pump is a mixing chamber which mixes the gas with the liquid to give sufficient weight or body to the propellant to allow the venturi principle to operate through the venturi section 40. The staging of the delivery tubing with gradually increasing sizes provides the same volume for the expanding gases. The high velocity gas is given body to act as a propellant force, thus increasing the surface effect of the high velocity mixture stream and the staging of the delivery tube so as to have increasing cross sectional dimensions utilizes the expanding gas energy to continue driving fluid after the velocity of the driving mixture is expanded.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. An induction pump for wells comprising a pump body having at least one opening therein for receiving a fluid to be pumped, a pressure gas inlet in said body, a hollow nozzle in said body having a velocity increasing orifice in its upstream end, an enlarged intermediate portion, and a velocity increasing restriction at its outlet end, said orifice being in communication with said pressure gas inlet whereby the flow path of gas is through said enlarged portion of said nozzle and out said restricted end, said nozzle including at least one aperture downstream of but adjacent said orifice establishing communication between said fluid and said gas flow path, and a venturi tube having its inlet end surrounding but spaced from said outlet end of said nozzle whereby said fluid and gas flow path are also in communication between said nozzle outlet and said venturi inlet.

2. Apparatus according to claim 1 wherein said body comprises an annular chamber surrounding and substantially concentric with said gas flow path, said chamber communicating with said gas flow path only adjacent said orifice and nozzle outlet.

References Cited UNITED STATES PATENTS 456,984 8/1891 Dailson 103-260 1,491,057 4/1924 Myers 193232 1,758,376 5/1930 Sawyer 103260X 1,902,728 3/1933 Schmidt 103-261X 2,675,081 4/1954 Nowak 103260X 3,216,368 11/1965 Waldron 103-260 3,302,586 2/1967 Brugnoli 103232 3,395,647 8/1968 Clabaugh 103-278 CARLTON R. CROYLE, Primary Examiner R. E. GLUCK, Assistant Examiner P0405" UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 3 ,558 Dated January 26, 1971 Inventor(s) H grass It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3 line 24, "ozzle" should read --nozz1e--.

Column 4, line 44, (Claim 1) before "said enlarged portion c said nozzle" insert --said orifice into-- Column 3 line 64 "interal" should read --interna1- Column 4, line 1, before "liquid gas" insert --the-- Signed and sealed this 26th day of October 1971.

(SEAL) Attest:

EDWARD M .FLETCHER JR ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Patents 

